ofproto: Implement OF1.4 Group & Meter change notification messages

This patch adds support for Openflow1.4 Group & meter change notification
messages. In a multi controller environment, when a controller modifies the
state of group and meter table, the request that successfully modifies this
state is forwarded to other controllers. Other controllers are informed with
the OFPT_REQUESTFORWARD message. Request forwarding is enabled on a per
controller channel basis using the Set Asynchronous Configuration Message.

Signed-off-by: Niti Rohilla <niti.rohilla@tcs.com>
Co-authored-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>

3 files changed, 53 insertions, 5 deletions

diff --git a/ofproto/connmgr.c b/ofproto/connmgr.c
index b1ba0c697..ef2c06fc4 100644
--- a/ofproto/connmgr.c
+++ b/ofproto/connmgr.c
@@ -1709,6 +1709,28 @@ connmgr_send_port_status(struct connmgr *mgr, struct ofconn *source,
     }
 }
 
+/* Sends an OFPT_REQUESTFORWARD message with 'request' and 'reason' to
+ * appropriate controllers managed by 'mgr'.  For messages caused by a
+ * controller OFPT_GROUP_MOD and OFPT_METER_MOD, specify 'source' as the
+ * controller connection that sent the request; otherwise, specify 'source'
+ * as NULL. */
+void
+connmgr_send_requestforward(struct connmgr *mgr, const struct ofconn *source,
+                            const struct ofputil_requestforward *rf)
+{
+    struct ofconn *ofconn;
+
+    LIST_FOR_EACH (ofconn, node, &mgr->all_conns) {
+        if (ofconn_receives_async_msg(ofconn, OAM_REQUESTFORWARD, rf->reason)
+            && rconn_get_version(ofconn->rconn) >= OFP14_VERSION
+            && ofconn != source) {
+            enum ofputil_protocol protocol = ofconn_get_protocol(ofconn);
+            ofconn_send(ofconn, ofputil_encode_requestforward(rf, protocol),
+                        NULL);
+        }
+    }
+}
+
 /* Sends an OFPT_FLOW_REMOVED or NXT_FLOW_REMOVED message based on 'fr' to
  * appropriate controllers managed by 'mgr'. */
 void
diff --git a/ofproto/connmgr.h b/ofproto/connmgr.h
index 7ef583ad8..8048424b7 100644
--- a/ofproto/connmgr.h
+++ b/ofproto/connmgr.h
@@ -168,6 +168,9 @@ void connmgr_send_packet_in(struct connmgr *,
 void ofconn_send_role_status(struct ofconn *ofconn, uint32_t role,
                              uint8_t reason);
 
+void connmgr_send_requestforward(struct connmgr *, const struct ofconn *source,
+                                 const struct ofputil_requestforward *);
+
 /* Fail-open settings. */
 enum ofproto_fail_mode connmgr_get_fail_mode(const struct connmgr *);
 void connmgr_set_fail_mode(struct connmgr *, enum ofproto_fail_mode);
diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c
index e6c03516e..c1301b5c1 100644
--- a/ofproto/ofproto.c
+++ b/ofproto/ofproto.c
@@ -5908,6 +5908,14 @@ handle_meter_mod(struct ofconn *ofconn, const struct ofp_header *oh)
         break;
     }
 
+    if (!error) {
+        struct ofputil_requestforward rf;
+        rf.xid = oh->xid;
+        rf.reason = OFPRFR_METER_MOD;
+        rf.meter_mod = &mm;
+        connmgr_send_requestforward(ofproto->connmgr, ofconn, &rf);
+    }
+
 exit_free_bands:
     ofpbuf_uninit(&bands);
     return error;
@@ -6575,20 +6583,25 @@ handle_group_mod(struct ofconn *ofconn, const struct ofp_header *oh)
 
     switch (gm.command) {
     case OFPGC11_ADD:
-        return add_group(ofproto, &gm);
+        error = add_group(ofproto, &gm);
+        break;
 
     case OFPGC11_MODIFY:
-        return modify_group(ofproto, &gm);
+        error = modify_group(ofproto, &gm);
+        break;
 
     case OFPGC11_DELETE:
         delete_group(ofproto, gm.group_id);
-        return 0;
+        error = 0;
+        break;
 
     case OFPGC15_INSERT_BUCKET:
-        return modify_group(ofproto, &gm);
+        error = modify_group(ofproto, &gm);
+        break;
 
     case OFPGC15_REMOVE_BUCKET:
-        return modify_group(ofproto, &gm);
+        error = modify_group(ofproto, &gm);
+        break;
 
     default:
         if (gm.command > OFPGC11_DELETE) {
@@ -6597,6 +6610,15 @@ handle_group_mod(struct ofconn *ofconn, const struct ofp_header *oh)
         }
         return OFPERR_OFPGMFC_BAD_COMMAND;
     }
+
+    if (!error) {
+        struct ofputil_requestforward rf;
+        rf.xid = oh->xid;
+        rf.reason = OFPRFR_GROUP_MOD;
+        rf.group_mod = &gm;
+        connmgr_send_requestforward(ofproto->connmgr, ofconn, &rf);
+    }
+    return error;
 }
 
 enum ofputil_table_miss
@@ -7211,6 +7233,7 @@ handle_openflow__(struct ofconn *ofconn, const struct ofpbuf *msg)
     case OFPTYPE_TABLE_FEATURES_STATS_REPLY:
     case OFPTYPE_TABLE_DESC_REPLY:
     case OFPTYPE_ROLE_STATUS:
+    case OFPTYPE_REQUESTFORWARD:
     case OFPTYPE_NXT_GENEVE_TABLE_REPLY:
     default:
         if (ofpmsg_is_stat_request(oh)) {